73 Jackpiner Carb to Pipe Clearance

[Boyd Riggs]

I have searched the message board for anything pertaining to this subject and not found an answer. I know this has been run across before and I'm sorry if I am rehashing old issues.
Jackpiner build date 3/73. Acquired in the usual "been sitting for 25 years shape" Tank, seat, carb, pipe, air box were not on the bike when I acquired.
I am assembling for an attempt for a start up and evaluation of parts and tweaking needed.
The Bing 84 32MM Carb is so close to the pipe that it would have to be cocked to one side to have clearance. What is the fix for the clearance?

[Dale Fisher]

First assumption is you have the rubber pipe mount on both the left and right sides?


Dale Fisher
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[Boyd Riggs]

Yes, mounts properly installed. Cylinder intake presently has the bolt on rubber adapter for carb mount. I have a non rubber adapter that is designed for the clamp on Bings. I will install it and use radiator hose for joint. Maybe it will allow the Bing to come forward enough to get Clearance. There was a Mikuni in a box that was a part of the loose goodies at purchase. The Mikuni is in poor condition. Missing parts. The Bing I have is in great shape. Just needing to get started right now for an assessment. Might install the Mikuni later. I know you guys have come across every scenario there is with these Penton's and I enjoy learning more about them everyday.

[Rocket]

I believe you should have a 30mm carb, maybe that body is a little smaller for clearance.

[Boyd Riggs]

That's probably the culprit. Bing I have is a 84/32/3214. I'll be better off just picking up a 32mm $85.00 Mikuni and tune. There is plenty of info on here about the swap. Thanks for the reply.

74 CR250M
76 RM370
74 1/2 Penton 250 Hare Scrambler
75 Penton 125
73 Penton Jackpiner
79 CR250R
80 Ktm 125
04 KTM 250 EXC

[KJDonovan]

Boyd,

Something else that may resolve this is the intake manifold.  I know there are a couple styles, some are straight (assuming yours is) and there are others that are angled slightly (about 20 degrees) to the right so the top of the carb clears the pipe.  I have one like this on my 250, without it the top of the carb would be hard up against the pipe.  With it, I have plenty of clearance.

Thanks,

Kevin

[Boyd Riggs]

Update:
Installed Mikuni. Fired up second kick. Tuned, runs like a champ. Of course I'll keep the Bing on the shelf for originality.

74 CR250M
76 RM370
74 1/2 Penton 250 Hare Scrambler
75 Penton 125
73 Penton Jackpiner
79 CR250R
80 Ktm 125
04 KTM 250 EXC